<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    题目1: 对字符串进行排列组合, 得到所有字符的全排列组合(假设所有字符不重复)
    函数名：permutation
    参数：需要排列组合的字符串
    返回值：字符串的所有排列组合数组
    例如：permutation("abc") 返回 ["abc", "acb", "bac", "bca", "cab", "cba"]
</body>

</html>
<script>
    function permutation(str) {
        let result = [];
        if (str.length <= 1) {
            return [str];
        } else {
            for (let i = 0; i < str.length; i++) {
                let a = str[i];
                let newStr = str.slice(0, i) + str.slice(i + 1, str.length);
                let b = permutation(newStr);
                for (let j = 0; j < b.length; j++) {
                    let tmp = a + b[j];
                    result.push(tmp);
                }
            }
        }
        return result;
    }
    console.log(permutation("abc"));
</script>